A common problem exists with decks of typical wooden construction. When a deck surface is constructed of wood, it is subject to rotting, warping, splintering, discoloration, deterioration and other tendencies inherent to the wood itself. Therefore, wooden decks must generally be frequently treated with a chemical preservative to help the wood withstand the effects of exposure to an outdoor atmosphere. Such treatment is usually very time consuming, costly and laborious, and typically must be repeated frequently. Additionally, even with proper treatment, there is no guarantee that the wood will not deteriorate. There are a number of reasons for this, including moisture present in the wood prior to treatment, areas of the wood which are difficult to access during treatment, and entry ways into the wood, such as nail holes, which allow moisture to intrude. Furthermore, the wood may also be damaged by temperature fluctuations leading to expansion and contraction, and by exposure to ultraviolet radiation via sunlight.
Once a wooden deck has begun to deteriorate there is generally little that can be done to halt the process. The typical solution is to remove and replace the wooden boards once they reach a point where their appearance can no longer be tolerated or they become unsafe. Replacement of boards is not only costly, but can also be difficult depending on the construction of the deck and the particular location of the damaged board. In addition, deteriorating boards can prove a danger, as they often produce splinters, result in an uneven walking surface. Also, the deterioration may occur from within causing the deck to become structurally unstable without appearing as such from the outside.
Many decks are being built now with composite or plastic planks which are either solid or cored. These products eliminate the problems of long term care of wooden decks, yet the cost is prohibitive as it is 2 to 3 times the cost of wood. Thus it would be highly desirous, to have a lower cost alternative to such plastic planks. Such an alternative would be to cover the surface of the planks of a wooden deck, whether or not it has already begun to show signs of deterioration, with an aesthetically pleasing and stable surface.
Early attempts at such a cover are disclosed in U.S. Pat. No. 4,885,882 (the '882 patent) to Forshee issued on Dec. 12, 1989 entitled “Deck Covering” and U.S. Pat. No. 4,907,387 (the '387 patent) to Turnbull issued Mar. 13, 1990 and entitled “Patio Deck Sheath”, the disclosures of which are hereby incorporated by reference. These plank covers comprise a flat top portion to cover the top of the plank and two flat side portions attached perpendicularly to either edge of the flat top portion to thereby cover the sides of the plank. These covers were innovative for their time, but deficiencies in their design and construction have come to light.
One such deficiency is that the cover must be fastened to the deck plank by some sort of fastener such as glue, nails or screws, etc. This fastening causes problems. First, the thermal expansion of the wood and the plastic coverings is substantially different. Thus, the temperature differential between summer and winter will cause the glued covers to break free and those fastened by nail or screw to warp and/or bulge. Also screwing or nailing through the cover allows moisture to enter through the covering and attack the wood underneath the covering resulting in unseen deterioration and rotting.
A second deficiency of these early covers stems from the fact that such wooden deck planks are not the same size (particularly weather treated lumber) throughout their entire lifetime. When the lumber is fresh out of the mill, it is a different size than when the plank has dried for a significant amount of time. Thus, once the glue holding the cover down has broken because of the stress of thermal expansion/compression or weathering, and the deck plank has shrunk with age, the cover will not be held in place by anything and will come loose. Also, the shrinkage of the wood over time means that multiple widths of the cover will be needed to accommodate the differing sizes of wood on different age decks, making production costs prohibitively high.
A later attempt to produce a plank cover is disclosed in U.S. Pat. No. 5,070,664 (the '664 patent) to Groh, et al. issued on Dec. 10, 1991 and entitled “Thermoplastic Cover for Stadium Seating, Picnic Tables, Boat Docks and the Like”, the disclosure of which is herein incorporated by reference. The cover disclosed in this patent has the same basic structure as the '882 and '387 patents, but adds “marginal flange portions” to the bottom edges of the side portions which are perpendicular to the side portions and extend partially inward toward each other. These flange portions are adapted and configured to engage the undersurface of the wooden plank.
Unfortunately this configuration while attempting to eliminate the deficiencies of the prior art, added additional deficiencies and retained others. First, in this configuration, the plank cover is deficient in that it cannot be added to existing structures. That is, because the flange portions engage the flat underside of the wooden planks, they cannot be placed onto the planks after the planks have been installed onto a deck. The covers must be placed on the wooden planks before construction of the deck. Thus, the deck fasteners (nails, screws, etc.) must be driven through the cover to construct the deck. This gives rise to the moisture leakage and thermal warping/bulging deficiencies of the prior art discussed above and once again, this cover structure does nothing to account for the shrinkage of the wood as it ages. Finally the cover structure must be cut/notched to accommodate joists, ledgers and other supporting structure to which the cover planks will be attached, thus complicating installation and construction.
Finally, a very recent attempt to design a deck plank cover is disclosed in U.S. Patent Application Publication 2002/0023395 (the '395 publication) A1 to Pasterchick, published Feb. 28, 2002 and entitled “Deck Master”, the disclosure of which is incorporated herein by reference. The cover has the same basic structure as the '882 and '387 patents, but adds locking tabs to anchor the cover to the under side of the wooden plank. These locking tabs seem to be very similar to the flange portions of the '664 patent and are adapted and configured to engage the undersurface of the wooden plank. Again, it seems that this configuration would require the covers to be placed on the wooden planks before construction of the deck. However, if not the cover structure must still be cut/notched to accommodate ledgers, joists and other supporting structure to which the cover planks will be attached, thus complicating installation and construction. Additionally, this cover design seems to have side panels that do not extend all the way down the edges of the wooden plank and therefore leave a portion of the wood exposed to the elements to deteriorate/rot. Finally, as with all of the previous designs, this cover design does nothing to account for the shrinkage of the wood as it ages.
Thus there is a need for a deck plank cover that can be applied over the planks of a new or existing wooden deck after construction thereby giving the benefits of a plastic or composite deck, for fraction of the cost. The plank cover should adhere to the wooden plank at any ambient temperature without the use of glue or fasteners and remain adherent even as the wooden plank it covers shrinks upon aging.